Method of and means for surface broaching



Sept.` 9, 1941. F .J LAPOINTE METHOD OF AND MEANS FOR SURFACE BROACHING File-d Sept. 2, 1957 3 sheets-sheet 2 Sept 9, l941- l F. J. LAPolN-TE METHOD OF bAND MEANS FOR SURFACE BROACHING 5 Sheets-Sheet 5 Filed sept. 2, 1937 l Pima-dl sepas, 1941 l wml "UNITED STATES ,PATENT ferries 2,255,2.21 Marnen or aluiomaligqsron seamen 'Francis i. Lapointe, Ann arbor, Mich.

by mesne assignments,

Machine Co., of Michigan Application September wisnor. to'AmericanBroaols b Ann Arbor, Mich., a corporation 1937, SerialNo. 162,178

The invention relates to aA method of and means for removing material, particularly adapted to surface breaching.

One object of my invention is the provision ef. a new and improved method for removing 'material from the surface of a work piece by operation ef a succession of breaching cuts, made fin different directions with respect te the surface.

Another object is the provision of a new and improved method for breaching the surface of 'a work piece which employs rst a series of Y between the series of cuts and still another group fer making a nnishing cut across the breached surfaceof the werk piece.

' A further object is the provision of a new and a series of breaches for making spaced cuts in the surface of the work piece,

series of breaches cutting in a different direction for removing the surface material remaining between the 'rst cuts.

Another object is the provision of a new and improved surface breaching device which em.-

ploys a group .of ,breaches for making a series of spaced cuts in the surface of a work piece, then employs another group of breaches for cutting away the material between the series of cuts originally made, and nally employastill a third group of breaches for making a finished cut across the surface breached by the combined ac- Y tien of the rst two groups of breaches.

Other objects and advantages of my invention will appear as the description proceeds taken in connection with Ythe drawings which form a part of this speciiication.

improved surface breach adapted to be inserted in a slot made in the surface of a work piece and. forced through a breaching stroke during which it operates to cut away material from one side of the slot while being braced against the opposite wall of the slet.

Still a further object is the provision of a novel surface breach having teeth positioned to cut in a direction .parallel te the surface te be breached and having .the teeth so constructedthat chips are tossed laterally o1' the breach itself and away Vfrom the surface which is being breached.

-A still further object is the provision of a plurality of surface breaches for making cuts in a direction parallel to the face ef the .work piece,l the plurality of breaches being divided into two groups, with each group inclined as a unit in ep posite directions so that during the cut the force exerted by one group upon thework piece is counterbalanced by the'force exertedon the werk piece by the other group.

An additional object is the provision of a new and improved breaching device for removing material from the surface of a work piece by the action of a succession of breaches adapted to make cuts in different directions with'respect te the surface.

Another object is the provisionlof a new and improved breaching device for removing material In the drawings:

Fig. l is a front elevation of the breaching device mounted on avertical breaching machine;

Fig. 2 is a side elevation of the machine shown in Fig. l;

Fig. 3 is a front Adevice shown detached from tbe machine;

Fig. 4 is a side elevation of the device shown innige;

5 5 at Fig. 3

Fig. 5 is a sectional view taken on the line looking in the direction of the arrows with the addition of a werk piece shown insectien; l

Fig. 6 is an enlarged side view ofthe device shown in section; l

33 Fig. 7 is' an enlarged sectional view taken. on

to a limited extent,

force required in breaching operations.

from the surface of a work piece which employs line 1 1 of Fig. 5 looking in the direction of the arrows; and

Fig. 8 isa fragmental elevation of the lower end ofy one of the central breaches.

While I have shown in the drawings and will herein describe in' detail the preferred embodiment ef my invention, it is to be understood that I do not thereby intend to limit the invention to the-specific form disclosed, but aim te cover all' modincations and alternative constructions falling within the spirit and scope ofthe invention as expressed in the appended claims.

While surface breaching has frequently been resorted to for removing material from the surface of a work piece, it has always been found in practice, that material could be removed only because of theconsiderable Diniculties have been encountered when it has been desired to breach a veryy large expanse of surand next another elevation of the breaching move material from a the use of a series ef groups c for a surface for reciprocating face at a single breaching stroke and also when single stroke breaching method which is operative, by reason of making cuts ef different character inte the surface of the work piece, to recensiderable expanse of surface and to an appreciable depth.

In the preferred form` described, this breaching method contemplates the cutting away ofthe surface of a work piece in different directions by of breaches, all mounted upon a single support se that the operation can be performed by a single stroke. A device for performing the 'method is shown in tiened in this manner are adapted to cut a series ofspaced slots or incisions 24 to a desired depth in the surface of the work piece I4 at right angles to the plane of the surface,

The second set of breaches I1 is positioned immediately above the lower set and consists of breaches separated `into two groups corresponding te the grouping of Athe lower set of breaches, each containinga plurality of individual breaches 25 in sufficient number so that there is one breach 25 fer each of the breaches in the lower set.

the drawings mounted upon a vertical breaching i machine provided with a bracket. at the front b upon which a work piece may be secured preparatory te a breaching operation. The first series of narrow spaced cuts is of surface breaches cutting into thesurface of the work piece in a direction at right angles to the surface. Material between the first cuts is removed by using a plurality of breaches having teeth on the lateral edges. These breaches are inserted individually, one in each slot and as the movement of the support continues .in a downward direction, this second series of breaches .proceeds by action of the lateral teeth te cut made by a lower group The two groups of breaches comprising the second set I1 are tilted towards each other at the tops, the angle of tilt being such that, taken with the length of the` occupies a position overlapping the slet adjacent. By this arrangement, it is made certain that all of the material remainingbetween the initially formed slots 24 is completely removed by action' of lateral teeth formed enthe. second set of breaches.

In order that'the breaching device may operate in the manner intended, the breaches 25 of the second set are constructed in a particular manner. Each of the broaches 25 has an'elengated body portion of substantially constant width provided with a projection 21 at the base receivable in a corresponding slet 28 in the backing to which it is securedV at the lower end by screws ll. and

at the upper end by abutting pins I2, the abutting of the breaches 25.

away said material remaining between each of the slots first made in the work piece. After the entire surface has been cut away, a finishing out is performed by a third set of breaches particularly designed as nnishing breaches which are passed over the newly breached surface of the work piece during a continuation of the stroke in order to leave the surface of the work piece in a nished condition. A

A means *for performing the method is shown in the drawings, consisting of a base Ill which supports a column er frame II for enclosing and supporting the operating parts of the machine. At the front ofthe frame Il is a bracket I2 te which is attached a tiltable werk support I3 shown in dotted position in Figs. 1 and 2, and upon the work support there is shown mounted a work piece I4 positioned in the machine ready breaching operation. Mounted at the front of the machine is a backing I5 upon which is attached a series of breaches. This series comprises, in this'embodiment of my invention, a lower set of breaches generally designated I5, an intermediate set ef breaches generally designated I1 and an upper set of breaches generally designated I4, all arranged to be moved as a unit through a single breaching stroke. 'A suitable power mechanism, not shown, is used the series of breaches in a vertical direction, so that there is a cutting stroke in the downward direction and a return stroke in the upward direction.

The lower set of breaches I5 comprises a plurality of vertical breaches arranged in two groups 2l and 2l on either side of the center line through the device consisting of individual breaches 22. These breaches are mounted upon the lower portion of the backing I5 in suitable slots and abut a brace 25 at the top,l with teeth 23 directed outward from the backing. The lower breaches posi- It' will be seen that each broach'25 has extending outward from the front face thereof a wedge shaped portion 35. The lewermest end or apex 38 of the wedge'shaped portion isy narrower in width than the corresponding width of each lower breach 22 as indicated in Fig. '1,.so that the apex I6 may t readily within the slet or cut breached bythe corresponding lower breach 22. In addition, one side 31 of the wedge shaped portion is straight and extends in line with 'the direction of the stroke of the breaching device. The edge 31 is also nat as shown in Fig. 5 and when inserted in its corresponding slot 24 acts as a brace for the breach by bearing directly against a side 35 of the slot. It will be seen also, by reference to Fig. 5, that the outward extending wedge shaped portion of the breaches 25 has such a thickness, that it enters completely into the slots 24 and is limited under ordinary circumstances to a depth flush with the bottom of the slet by reason of a laterally extending portion 424 of the breach becoming ush with the outer surface 35 I4 which is being breached. Should the depth of the slot 24 result less than the thickness of the protruding wedge shaped portion 55, the breach is prevented from cutting deeper than the depth ef the slot by contact of the outer face of the wedge shaped portion 35 with the bottom.

The other edge of the wedge shaped portion of the breach 25, opposite from the fiat edge 51, has a series ef breaching teeth 40 cut therein and' so arranged that a line drawn through the'cutting y edges of the teeth is inclined from the perpenbreach.' the top of each breach Vfinishing set of breaches I 8 accesar a the breaching device is forced downwardthrough its breaching stroke, the iiat side 3l of the wedge shaped portion, of'the breach is braced against one side 38 of its corresponding slot 24 and forces the opposite toothed edge of the wedge shaped portionv against the opposite side 38' of the cut 24 4to assure a positive breaching stroke for clearing away all of the material between the-slots.

It is significant that the teeth l of the breaches have the cutting edges and a portion of the undercut of each pitched sidewise at 4I in an inclined direction with respect tothe breach itself, as best seen in Fig. 6. By constructing the teeth in this manner, chips of metal cut from the surface of the work piece are tossed in a lateral direction with respect to the breach and outward from the face of the werk piece in such a manner that they-will not clog the teeth of the breaches during the cutting stroke. This is important in view of the fact that such a large quantity ef material is cut from the surface of the work piece at one time.

groups tilted in opposite directions. By such an arrangement, the force exerted bythe cutting action of the teeth of one of the groups of breaches, which would ordinarily tend to shift the work piece laterally in the machine, is ceunterbalanced by the force exerted by the cutting action of the teeth in the group of breaches at the oppositeside. It will, therefore, be apparent that the thrust exerted by the cutting action of all of the breaches is actually made use of in securingthe work piece positively in alignment during the cutting stroke and is at the same time instrumental in balancing the strain on the backing for the breaches.

After the bulk of material hasbeen removed from the surface of the werk'piece, the third o'r is passed through a breaching stroke. This nishing set is comprised of individual breaches 66 which are secured in slots dl of the backing l5 by means of screws t6.- The breaches extend completely across the face Y of the support l5 and are inclined slightly from the horizontal so that a slicing cut is made during the nisli stroke. By reason of the fact that these last breaches extend the entire distance from one side of the device to the other, a smooth level cut is made in the werk piece deep enoughl only to remove any reughnessin the surface with the result that a perfectly plane finished surface is produced on the work piece l t.

-In the structure described, there has thus been disclosed a breaching teel or device comprising a plurality of parts arranged in a particular manner to make possible the breaching of large areas ef the surface of a werk piece at an appreciable depth in such a manner that the operation can.l

be completely iinished in a single working stroke of the breaching machine. I claim as my invention:

1. 'Ihe method of removing surface. material l' from a werk piece te a desired depth comprising placing the work piece in a fixed` position, breaching a plurality of spaced slots in the surface thereof withone set of breaches, placing-individual breaches comprising`anether set one in each of said slots, bracing lthe breach in eachv 2. A-multiple breaching tool for cutting away a portion of the surface of a work piece comprising a support or backing for the tool, means forming a first set of breaches for breaching ya series of spaced cuts into the surface of the work piece,.means forming a second set ofk breaches comprising individual membersy having portions adapted te engage the spaced cuts, said portions having lateral cutting edges tilted slightly from the vertical for breaching away the surface portions intermediate 'the first cuts.

3. A multiple breaching tool for cutting away a portion of the surface of a work piece comprising a support or backingfor the tool, means forming. a first set breaching a series of spaced cuts into the surface of the werk piece, means forming a second set of breaches comprifing' individual members having cutting portions adapted to engage the spaced cuts,v said portions having lateral cutting edges tilted slightly'from members being balanced in two groups with their respective cutting edges positioned in opposite directions for breachinga series of cuts intermediate the rst series of cuts.

4.- A compound breaching tool for operating on the surface of a work piece comprising a first cutting means for cuttingthe sides and bottom of a slot inthe surface'of the work piece, a second side of lthe slot, and theother edge supplied with teeth for cutting away the other side of the slot.

5. A compound breaching tool for operating on the Asurface of a work piece comprising a rst breaching means for cutting out the sides and bottom of an initial slotk in the surface of the work piece, a second breaching means for making arcut at an angle to the cut made by the first means including a wedge shaped portion having one edge extending vertically in the same general direction as the first breaching means operable as a brace against one side of the slet, and the other edge supplied with teeth disposed on a line at an angle with the first edge for breaching away the other -side of the slot, the apex of said wedge shaped portion being of a width narrower 7. A breaching tool for removing material from the surface of a work piece comprising al bed like support having a recess therein, a body havinga base portion at one side adapted to be secured to the support within the recess and having a protruding wedge shaped portion at another side, said wedge shaped pertionhaving an edge provided with breaching teeth extending laterally therefrom, said teeth having a portion at the undercut pitched sidewards at an angle so as to of vertical .breaches forthe vertical, said individual s piece comprising a body narrow end, 'said portion throw chips laterally of the teeth and outward from the surface of the work piece.

8. A device for removing material from the slotted surface of a work piece comprising a broachingv tool having a body including a longitudinally disposed wedge shaped portion thereon.

` surface of a work piece provided with a vertical slot comprising a broaching tool having a'body of uniform maximum thickness including a longitudinally disposed wedge shaped portion on the outward face of the body and a laterally extending part` of said body depressedbelow the face of the Wedge shaped portion. the apex of said wedge shaped portion being sufficiently nar# row to permit entrance thereof into the vertical slot of the body, said entrance being limited to a depth determined by contact of the laterally extending part of the body with the surface of the Work piece, said wedge shaped portion having teeth formedI in an edge thereof and extending laterally therefrom to cut material from the work piece in a direction parallel to the surface thereof.

10. A multiple single stroke broaching tool for cutting away' a portion of the surface of a work piece comprising a support or backing for the tool having groups of vrecesses formed therein, means forming a having projections thereon engaging one of said groups of recesses for broaching a series ''f spaced cuts into the surface of the work piece, and means forming a second set of' broaches having projections thereon for engaging another of saidfgroups of recesses comprising individual members each` provided with a lateral cutting 'edge tilted slightly from a vertical position bearing broaching teeth adapted to engage the spaced cuts, said teeth having a portion at the undercut pitohed-sidewards at an angle so as to throw' chips laterally of the teeth away from the suiface-ofthe -work piece, the individual'members of the second set of broaches-being balanced in two groups with their respective cuttingedges positioned in opposite directions for broaching a first set yof! vertical broachesthe cuts made by the first series of broaches comprising a plurality ofindividual broaches, one insertable in each of said initial slots. each broach including a wedge shaped portion having one edge extending vertically in the same general direction as the sides of the initial slot operable as a brace against one of said sides, and another edge supplied with teeth disposed on a line at an angle with the first edge for broaching away the other side of the'slot, and a laterally extending shoulder portion adjacent one of the edges set back from the face of the broach, :the apex of each of said wedge shaped portions being sufliciently narrow to permit admission into-its respective initial slot, said admission being limited to a depth determined by contact of the laterally extending shoulder portion with the normal surface of the workpiece, and another group of finishing broaches attachable to the backing for finishing the portion of the surface of the work piece jointly broached by the preceding two' series of broaches.

12. A tool for surface broaching comprising a support, a first broaching means composed of a plurality of individual laterally spaced and parallel broaching elements operable to cut a lplurality ofl incisions into the surface of the work piece, and asecond broaching means composed of a plurality of broaching elements one for each of the broaching elements in said Irst broaching means, each of the elements of said second broaching means being operable to engage a side i wall of the incision formed by the corresponding element. of the first broaching means to broach across the workpiece at the depth of the incision in the work piece, thetrailing portion of each of` said-elements .of said second broaching means extending laterally beyond the adjacent side wall of the'adjacent incision so as to be operable to remove all of the material between the adjacent incisions.

13. A tool for surface broaching comprising a support, aflrstbroaching means composed of a plurality of individual parallel and laterally spaced broaching elementseach having progressively extending teeth operable to form a narrow slot in the surface of a work piece during longiseries of cuts intermediate the first series of cuts.

11. A compound single stroke broaching tool for broaching and finishing the surface of a work piece comprising a backing for the tool, afirst series of surface broaches attachable to th' backing'for cutting out the sides and bottom 'of" a series of initial slots in the surface of a work piece, a second series of broaches attachable to the backing for making cuts at right angles to tudinal movement of'v 'the -tool, and a second broaching means composed of a plurality of elongated, generally longitudinally disposed and parallel broaching elements, one for each of the elements in said first'means, each of the broaching elements of said second means having a plurality of 'teeth formed on a face disposed at right angles to the toothed face of the elements of saidflrst broaching means, said teeth projecting laterally progressively away from said first broaching means with the adjacent tooth receivable within the slot formed by the corresponding element of the first means and the remote tooth extending laterallyl beyond the opposed face of the adjacent element of said first means.

lltAIICISY J. LAPOINTE. 

